Photo exchanging device

Abstract

Abstract PURPOSE: To obtain the exit light having always constant dynamic range by adjusting the ultrasonic power in the acousto-optic element until the detection level of the primary diffracted light in the medium and a set reference value coincide thereby performing light intensity modulation. CONSTITUTION: When the code signal of a photo exchanging command is entered to an acousto-optic element AO, the zero order diffracted light thereof is applied to the element AO via sensor PS1, code converter 5', VCO6 and the amplitude modulator 12 of a light intensity modulation control system B, the diffraction angle θ of the primary diffracted light whereof is then adjusted and is selectively emitted to arbitrary optical fibers F 1 thru F 3 . In this case, the primary diffracted light is detected through a half mirror HM and sensor PS2 and the detection level V 2 thereof is compared with a set reference voltage value VS. The output of the modulator 12 is then increased until V 2 and V s coincide, whereby the light intensity modulation of the element AO is accomplished. As a result of this, the primary diffracted light of the element AO may be maintained at the specified intensity level. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Masaaki Mori

Bibliographic Details